This invention relates in general to vehicles and, in particular, to the operator's seat assembly of vehicles, such as construction and industrial machinery.
More specifically, but without restriction to the particular use which is shown and described, this invention relates to a support structure for the operator's seat of a vehicle, such as in an earth moving machine and the like. The improved seat support structure of the invention permits the seat assembly to be locked in stable and proper position for use by an operator in operation of the vehicle. The seat assembly is further releasable for pivotal movement about a pair of parallel axes for allowing unimpeded accessibility to the components of the vehicle, which are normally situated beneath the floor or frame under the operator's driving position.
In vehicles, such as construction machinery in the form of earth moving equipment and the like, the operator's seat is typically located at a position above many of the operative and control components of the vehicle, such as the hydraulic control devices for controlling various mechanical functions, the vehicle transmission, and the like. In the prior art, conventional seat assemblies have been attached to the vehicle in a manner to impede inspection or service of the vehicle components situated beneath the operator. Many past seat structures require the cumbersome and inconvenient disassembly of the seat components from the vehicle frame to permit such access to areas under the seat. Upon removal of such known seat assemblies, it is then possible to remove the panels and various structural parts of the vehicle to expose the vehicle mechanisms beneath the floor.
The requirement for removal of the seat structure through complete or partial disassembly has proven to be highly unsatisfactory and an inefficient operation. Attempts in the prior art to eliminate the necessity of disassembly or detachment of the seat and support from the vehicle, have also been ineffective. One such technique has employed a seat frame which is pivotally mounted about a single horizontal axis, such that the area of the vehicle beneath the assembly may be exposed. The pivotal support of the seat assembly about a single axis has at best only allowed limited accessibility to the components beneath the operator's position, because even in a rotated position, the seat structure generally includes protruding structural portions, which inhibit accessibility. Thus, because of the physical size of the seat assembly and its associated structural components, it is virtually impossible to attain satisfactory accessibility beneath a seat by mounting the structure for rotation about a single limited axis. The prior art assemblies having such a limited pivotal capability have also not been provided with effective latching mechanisms facilitating securement and release of the seat as circumstances required during use of the vehicle. Typical seat assemblies mounted for a limited degree of selected pivotal movement are disclosed in U.S. Pat. No. 3,095,232 to Stevens, issued July 25, 1963 and U.S. Pat. No. 3,463,542 to Daniels, issued Aug. 26, 1969.